Distributed Coordination of EV Charging With Renewable Energy in a Microgrid of Buildings

With the rapid development of electric vehicles (EVs), the consequent charging demand represents a significant new load on the power grids. The huge number of high-rise buildings in big cities and modern technological advances have created conditions to mount on-site wind power generators on the buildings. Since modern buildings are usually equipped with large parking lots for EVs, it shows vital practical significance to utilize the on-site wind power generation to charge EVs parked in the buildings. In this paper, we first use a case study in Beijing to show that the on-site wind power generation of high-rise buildings can potentially support all the EVs in the city. Considering that the charging demand of EVs usually does not align with the uncertain wind power, the coordination of EV charging with the locally generated wind power in a microgrid of buildings is investigated and three main contributions are made. First, we investigate the problem and formulate it as a Markov decision process, which incorporates the random driving requirements of EVs among the buildings. Second, we develop a distributed simulation-based policy improvement (DSBPI) method, which can improve from heuristic and experience-based policies. Third, the performance of the distributed policy improvement method is proved. We compare DSBPI with a central version method on two case studies. The DSBPI method demonstrates good performance and scalability.